Which RDBMS do you use in your day-to-day work?

While having a discussion in a team meeting last week, a question came up about client shops using more than 1 RDBMS and hence the need for the consultants to know more than one RDBMS so that they can help the clients better. So, here’s a poll to end the week – which RDBMS do you use in your day-to-day work? This is a multiple choice question and we have listed the popular RDBMS over here.